Discoverer 17, also known as Corona 9012, was an American optical reconnaissance satellite launched on 12 November 1960 at 20:38:00 GMT.

[1] Discoverer 17 was the second of the KH-2 Corona spy satellites, which was distinguished from the predecessor KH-1 series in its incorporation of the improved C' camera, which replaced the C model carried on KH-1 missions.

The improved camera had variable image motion compensation so that its carrying satellites could be flown in differing orbits.

[4] The satellite had a mass of 1,091 kilograms (2,405 lb),[5] and was equipped with a panoramic camera with a focal length of 61 centimetres (24 in), which had a maximum resolution of 7.6 metres (25 ft).

Unexpectedly high radiation levels during the flight led to the data from this experiment being considered particularly valuable by US Air Force scientists.